If you are still a beginner in this industry, then Bitcoin is the best choice for you, the problem of limited basic capital is not an obstacle for you to invest in Bitcoin because the units can still be broken down into the smallest parts (Sat).
We do not know if OP has enough capital to continue making periodic purchases because he only mentioned having a small capital. I saw OP's previous post, and he only said he has $20. It is uncertain whether he allocates that amount weekly or monthly from his work earnings.
Hopefully, OP is not thinking of using his money to buy shitcoins with $20 and hoping it will turn into $200 or $2000 in a short time. Giving advice to buy Bitcoin is very good, but investments should be based on knowledge and a plan. OP may need to do a few things first before starting.